Wireless communication has become an integral part of modern life in personal and professional realms. It is used for voice, data, and other types of communication. Wireless communication is also used in military and emergency response applications. Communications that are made wirelessly rely on the electromagnetic spectrum as the carrier medium. Unfortunately, the electromagnetic spectrum is a limited resource.
Although the electromagnetic spectrum spans a wide range of frequencies, only certain frequency bands are applicable for certain uses due to their physical nature and/or due to governmental restrictions. Moreover, the use of the electromagnetic spectrum for wireless communications is so pervasive that many frequency bands are already over-crowded. This crowding may cause interference between and among different wireless communication systems.
Such interference jeopardizes successful transmission and reception of wireless communications that are important to many different aspects of modern society. Wireless communication interference can necessitate retransmissions, cause the use of ever greater power outlays, or even completely prevent some wireless communications. Consequently, there is a need to wirelessly communicate with reduced electromagnetic interference that may hinder the successful communication of information. Use of horizontal polarization may improve communications reliability by reducing interference from predominantly vertically polarized signals in overlapping and adjacent frequency bands. Conversely the application of vertical polarization in an environment dominated by horizontally polarized interference may improve communications reliability.
Multipath fading results in reduced communications reliability, particularly where mobile devices pass through signal fades. Linearly polarized communications systems may generally be more susceptible to multipath fading than elliptically or circularly polarized systems. Mobile systems typically require an omni-directional antenna pattern on the client devices. An omni-directional antenna is characterized by an azimuthal radiation pattern that exhibits minimal antenna gain variation. Horizontally polarized omni-directional mobile antennas are rare and not readily available in the industry. Circularly polarized omni-directional mobile antennas are rarer still.
The continued drive toward miniaturization and the ubiquitous nature of wireless communication creates a need for small antennas. A properly sized and designed antenna may be retrofitted into existing installations or into applications which are small by their nature. An antenna that is compact, and still able to transceive circularly polarized signals efficiently, allows for the use of circular polarization in applications that would otherwise be difficult to implement unobtrusively.